Page:Cyclopaedia, Chambers - Supplement, Volume 1.djvu/969

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. L A K

L A M

fixteen feet, in the fteep banks of the neighbouring river Beuly, there are found oak trees and pieces of burnt timber. We find by this, that the face of the whole country hereabouts is very different from what it was fome ages ago; and there feems fome refemblance between the prefent face of things here, and that in the bogs of many parts of England. The trees found buried in thefewere felled by the conquering Romans, and perhaps thefe are of fome fuch origin. "We have many angularities offering to our view in the lakes of our own country: that of their freezing at peculiar feafons js not one of the leaft. There is a little lake in Straherrick in Scotland, which never freezes over before the month of February, though the froffs be ever fo intenfe ; but after the firft part of this month, one night's trifling froft will cover it all over with ice, and a fecond night will induce it to a very confiderable thicknefs. There are alfo two otiier lakes in the fame county, the one called Loch Manor, which is confiderably large, yet always keeps up the fame rule of freezing over in February with every little froft, but never before that month be the feafon ever fo rigorous ; and the other in Straglafh, which is as remarkable for a contrary quality. This lies in a fort of bottom, between the fides of two very high hills, and is itfelf confiderably above the level of the reft of the country. This lake freezes continually. It has always ice in the middle, even in the hotteft fummer months, though it thaws about the edges. The fun by reflection from the hills on each fide of this lake gives a very confiderable heat ; and there are many other lakes in the fame fort of iituation, in the neighbouring country, which yet have nothing of this phenomenon ; fo that this, and the property of the other lakes, muff, be owing to fome thing peculiar to themfelves, not to their fituation, or other acci- dents. The herbage about the fides of this laft mentioned lake is in a fort of perpetual (bring all the year round, and is much eftcemed by the country people, being found to fatten cattle more in a week, than the belt land in the country befide will do in a fortnight. The lake is very deep, and the water does not manifdt any particular quality. Phil. Tranf. N° 114. The ftrange effect of fome lakes on their water being dif- turbed, are recorded by many writers with an air of truth ; but are to be examined, with great caution, before they are credited. Wagner, in his hiltory of Swifierland, quotes no lefs than thirty-five authors, who fay, that a water there called the lake of Pilate is of this kind, and that it caufes tempefts, rain, thunder, tffc. if any thing be caft into it ; but the truth is, that it is a very tame puddle, fcarce deferving the name of a lake ; and it is proved, by experience, that no confequence at all attends the throwing it into confufion by any means whatever, lVagmr% Hift. Helvet. Subterranean Lakes. That there are in many places im- menfe fubterranean lakes, can fcarce be doubted, becaufe we fee them in fome places ; but their effects are often perceived where they are not fcen, and puzzle the people who at- tempt to account for thofe effects upon other principles. The famous Zirchnitzer lake in Carniola, which fills and empties itfelf, at times, in an impetuous manner, bringing up with its waters fifh, and even wild fowl, communicates with another immenfe fubterranean lake in the mountain Javornick ; and according to its filling or emptying, the upper one is alfo filled and emptied. The grotto podfpetfehio, in the fame country, gives another inftancc of fuch a fub- terranean lake. The people of the neighbouring country enter the fide of the mountain where this lake is by a fmall open- ing, through which they go to a cavern of a great width and heigh th ; and at the end of this is a fmall opening again, through which they go on to the edge of a vaft fub- terranean piece of water. They go with torches, and find the water very clear and fine. It is ten cubits deep at the edge, and doubtlefs is much more in the middle. The water runs into this lake by a large channel, and runs out of it again by another, falling down a precipice into another lake, and that with fuch a noife, that the report of a piftol cannot be heard near it. Stones thrown in every way are heard to fall into water, and there is great reafon to fuppofe the lake a German mile long; for at that diftance there is another water difcovcred through fuch another cleft of the rock, which ftands at the fame horizontal height as this, and is fubject to the fame accidents at the fame times. This vaft body of water fometimes all runs off in a few minutes and leaves the bafon dry, and after fome weeks it fills again with a frightful noife. As thefe accidents always hap- pen to both the waters above-mentioned at the fame time. they appear very plainly to be only the two fides of the fame lake. Phil. Tranf. N 01 igi.

We have in England many of thefe refervoirs, the water of which is always remarkably clear and cold, and is fo loaded with fpar, that it generally encrufts things very quickly that are put into it ; and when raifed into vapours, as a part of it fometimes is, by the fubterranean heat, or carried up with other vapours, Itops at the cieling of the vaults, and there forms ftalactitse and other fuch concretions. In many of thefe lakes alfo are found the round balls of fpar, called italagnictse. They are compofed of feveral crufts gathering Sti PPL. Vol. I.

round fome central nucleus, and often exceed the fize of a fchool boy's maible. Phil. Tranf. N p 144. In Pen-Park hole in Glouceltermire there is a remarkable inftance of this, that ftrange cavern containing one of the largeft of the lakes in our kingdom. The hole itfelf was accidentally difcovered by fome miners, who were digging for lead ore ; it is twenty nine fathoms deep from the fur- face, and is a vaft cavern of the fhape of a horfe-fhoe, fur- rounded with rugged rocks and rough walls of earth, con- taining in the midft a river or fubterranean lake of twenty- fat horn broad and eight fathom deep, of the fame cold and petrifying water with the other refervoirs of this kind. The people oi the country have an opinion that this water ebbs and flows with the tide, but it is an error. The water is higher in winter and lower in fummer ; but the decreafe is ilow and gradual at the proper feafon, and fo is the increafe, ne- ver happening at any other time. There is in one part of the cieling of this cavern a vait hole, in at which fome mi- ners have crept, and faid they found lead ore very fine, and in great quantities ; but an idle opinion of fpirits pre- vents their purfuing the difcovery. The flooring of this vaft cavern is all of a white fparry ftone, fpangled over with lead ore ; and the rocks, which hang over head, are ail glazed, as it were, with fpars very bright and pellucid, and of very elegant figures. The higheft part of the roof is nineteen yards above the level of the water, and there are two large rocks in it, all covered with mud at fuch times as the water is nut above them, as in fummer it never is* The paffaees down into the hole, and the fide cavities, are all covered with that fort of fpar, which ufiially attends lead ore, and there is no living creature found in the place ex- cept fome bats. The air in the dcepeft part is clear, and the place lefs damp than might be expected.

Lake, orLAcvuE, a preparation of different fubftances into a kind of magiftery for the ufe of painters. One of the fineft and firft invented, of which was that of gum lacca or laque, from which all the reft, as made by the fame p:o- cefs, are called by the common name laques. The method of preparing thefe, in general, may be known by the example of that from the curcuma root of the fnops, called turmeric root, the procefs for the making of which is this. Take a pound of turmeric root in fine powder, three pints of water, and an ounce of fait of tartar : put all into a glazed earthen veffel, and let them boil together over a clear gentle fire, till the water appears highly impregnated with the root, and will ftain a paper to a beautiful yellow. Filtre this li- quor, and gradually add to it a ftrong fulution of roch alum in water, till the yellow matter is all curdled together and precipitated: after this pour the whole into a filtre of paper, and the water will run off and leave the yellow mat- ter behind. It is to be wafhed many times with freih water, till the water conies oft" infipid, and then is the beautiful yellow, called laque of turmeric, and ufed in painting. Shatu's Lectures, p. 17S.

In this manner may a laque be made of any cf the tinging fubftances that are of a fomewhat ftrong texture, as madder, logwood, &c. but it will not fuccced in the more tender fpecies, as the flowers of rofes, violets, CSV. as it deftroys the nice arrangement of parts, in thole fubject s, on which their colour depends.

A yellow lake for painting is to be made from broom flowers in the following manner. Make a lee of pot-afhes and lime reafonably ftrong \ in this boil at a gentle fire frefh broom flowers till they are white, the lee having ex- tracted all their colour ; then take out the flowers, and put the lee to boil in earthen veflels over the fire ; add as much alum as the liquor will diflblve ; then empty this lee into a veffel of clean water, and it will give a yellow colour at the bottom. Let all fettle, and decant off the clear liquor. Wafh this powder, which is found at the bcttom, with more water, till all the falts of the lee are wafhed off; then feparate the yellow matter and dry it in the ihade. It proves a very valuable yellow. Neri's Art of Glafs, p. 162.

LAMAC, a word ufed by fome authors to exprefs gum arabic.

LAMARE, a word ufed by fome of the chemical writers as a name for fulphur.

LAMB (Gee/.)— "Lamb earth, in hufbandfy, is a whitifh ftony loam.T'he name feems only a corrupt ion of the word ham earth. It is a clay, with an admixture of that fort of ftony matter which ufually conftitutes lime ftone, of fragments of lirhe! ftone, and of many fmaller pieces of a ftony matter, of a lefs firm concretion. Thefe ftones arc all of much the fame co- lour with the earth, and the whole eafily breaks and moul- ders upon putting water to it. It has ufually an admixture of fea fhells alfo in it, and, while in the ftratum, is fo hard as fcarce to be cut by a fpade. It is in great efteem in many counties of England for making the earthen floors of barns, and other fuch ufes. Mvre ton's Northampt. p. 67.

LAMBENT/™. See the article Fire.

LAME, in the manege, is ufed in feveral phrafes of that art - f

as lame of an ear, called in French boiteux de Toreille, is

faid ©f a horfe, when he halts upon a walk or trot, and.

15 D keeps